Jason Segel's Jeff is a slacker mooch. He's thirty; he's never left home, never dated after high school, and spends all of his time as a toilet Jungian getting high, watching infomercials, and trying to find meaning in his life because “Everyone and everything is interconnected in this universe.” The guy's a mess, but he's an earnest mess. In some ways, he's the modern version of Candide. Unlike Voltaire's old hero, Jeff can recognize and feel pain (and be set back by it), but he also exudes a certain unstoppable passion for meaning. He loves the movie Signs, and when the universe seems to be giving him a series of signals about some guy named Kevin, Jeff embarks on ridiculous, yet well-crafted slapstick journey for answers.

One morning, as he goes about his usual slacker routine, a belligerent stranger calls looking for a guy named Kevin, and he won't take no for an answer. Discombobulated by the event, Jeff tries to decipher the message when his mom (Susan Sarandon) calls, nagging him to do a favor for her. Though he's not pleased with the interruption and begins to fall into a fit of adolescent whining, Jeff shuts up when mom threatens to kick him out and begrudgingly sets off to take care of the chores.

But he's quickly derailed when a kid hops on the bus with a jersey that has “KEVIN” written along the back. In a flash, his task is forgotten and Jeff travels the city following clues he's sure will lead him to some important moment of meaning. As much as we'd like to chide Jeff for his optimism, he seems to be onto something as this journey keeps leading him back to his brother Pat (Ed Helms), whose marriage (to Judy Greer) is falling apart. Jeff tries to help his brother and also find the meaning of “Kevin,” all while mom keeps trying to reach her sons and deal with a secret admirer who keeps sending her flirty instant messages.

It's a ridiculous setup that could easily become tiresome or cliché if not for the mixture of pitch-perfect casting and brotherly sincerity. Jason Segel was born for this part. He's a large and seemingly out of place man who possesses a wildly potent aura of sweetness. That presence imbues Jeff with such earnestness that you immediately begin to feel for him – not as a stoner journeying through a good time a la Smiley Face, but as someone with a big heart whose quest becomes our own. Likewise, Helms stands up well against Segel, the typical good-on-paper son who might have a wife and job, but is utterly consumed by his own whims and desires, while Greer gives life to a wife surprisingly with such a loser, and Sarandon manages to make a fairly run-of-the-mill interlude play quite genuinely (she's helped by the lively Rae Dawn Chong).

The Duplass Brothers (Mark and Jay) thrive best when they get to share their brotherly connection on the big screen. In Your Sister's Sister (capsule review coming soon) it helped Mark Duplass star as a man mourning his brother's death, and in the realms of Jeff, Who Lives at Home, the Duplass bond adds a genuine grounding influence to the adventure, especially when Jeff must partner up with Pat, the all-out selfish jackass. This understanding of the connection between brothers and family members infuses every bit of comedy and plot in Jeff, making it a much more dynamic and worthwhile experience than their previous film, the squirm-bomb-ridden Cyrus.

There are still many squirms to suffer throughout the film, especially between Pat and his wife, but they're balanced by the comedy of an earnest journey. For what seems to be a fairly simple funny movie, there are a lot of layers to dig into – questions about optimism and meaning, about actions and intent, about how we judge people and fear being judged, about whimsy and real life. We're immediately told to look down on Jeff, because he lives at home, but we continually find ourselves drawn to him. He offers absurdity and integrity with every moment. And as Jeff sets off on his journey, he does so without the indie shackles of mumblecore. This is the Duplasses' most mainstream film yet -- not in a thematic way which could speak negatively about the film itself, but in its execution. Although still indie-intimate, the filmmakers now embrace a much larger scale, not only with a large selection of locations, but also stunts and heroics. It's a larger canvas that they handle extremely well.

Jeff, Who Lives at Home is a film that beautifully offers depth to those who thrive it, and easy comedic adventure to those looking for simply enjoyable entertainment. It's never empty, never easy, and never exactly what you'd expect.

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